Abstract

With the dc reactive magnetron sputtering method, conducting ZnOthin films with different carrier concentrations on glass substrate were fabricated. The dielectric responses of the ZnOfilms are characterized with terahertz time-domain spectroscopy. Frequency-dependent conductivity, power absorption, and refractive index are obtained, and the experimental results can be well reproduced with the classic Drude model. Our results reveal that by adjusting the carrier concentration of the ZnOfilm, the conducting ZnOfilm can serve as broadband antireflection coatings for substrates and optics in the terahertz frequency range.

Received 10 September 2008Accepted 05 November 2008Published online 24 November 2008

Acknowledgments:

This research is supported by National Natural Science Foundation of China (Grant Nos. 10774099, 10334030, 60225004, and 60221502), The Program for Professor of a Special Appointment (Eastern Scholar) at Shanghai Institutions of Higher Learning. The authors would also like to acknowledge the support of Shanghai-Applied Materials Research and Development Fund (Grant Nos. 07SA13 and 06SA05). Part of this work was also supported by The National High Technology Research and Development (Grants No. 2006AA12Z135) and Shanghai City Committee of Science and Technology (Grant No. 06XD14020).